Question

1. choose the best answer. what is a period? a row of elements a column of elements a block of elements a family of elements 4) choose the best answer. what is a group? a block of elements a row of elements a column of elements a triad of elements

Explanation:

• In the periodic table, a period is defined as a row of elements. Elements in the same period have the same number of electron shells.
• A group is a column of elements. Elements in the same group have similar chemical properties due to having the same number of valence electrons.

Answer:

1. a row of elements
2. a column of elements